A polymethylmethacrylate–collagen filler is generally believed to give long-term benefits, but the risk of granuloma formation over time remains unclear.OBJECTIVE
To determine the incidence of granuloma formation and response to treatment and assess the degree of patient satisfaction over 5 years.MATERIALS AND METHODS
Adults seeking correction of nasolabial folds underwent up to 3 injection sessions over 2 months. Subjects were then queried regularly for the development of signs and symptoms of a granuloma. Any positive responses were evaluated, and lesions suspicious for granulomas were confirmed by biopsy. Granulomas were treated at the discretion of the investigator. Subjects also completed regular satisfaction questionnaires.RESULTS
A total of 1,008 subjects were enrolled and 871 completed the full 5 years of the study. A biopsy-confirmed granuloma developed in 1.7% of subjects. Almost all granulomas responded to treatment. At study exit, 0.9% of subjects had an unresolved granuloma. Patient satisfaction remained high throughout the duration of the study.CONCLUSION
The incidence of granuloma formation with a polymethylmethacrylate–collagen dermal filler is low, and almost all lesions are manageable with simple therapeutic measures. Patient satisfaction remains durable over 5 years. Polymethylmethacrylate–collagen offers a well-characterized and very favorable risk/benefit profile.